Data API
This service facilitates machine-to-machine access to aviation weather information. These pages describe how to use the API and the interactive interface under Specifications can be used to learn more about available data, configure specific queries, and try them out. The weather database currently allows access to up to the previous 15 days of data.
Please keep requests limited in scope and frequency. Maximum results per query apply as well as rate limiting against frequent requests. For larger queries, please consider using the cache files which provide quick access to complete datasets.
Products
Product | Description | Coverage | Formats |
---|---|---|---|
METAR | Terminal observations | Worldwide | Raw text, JSON, GeoJSON, CSV, XML, IWXXM |
TAF | Terminal forecasts | Worldwide | Raw text, JSON, GeoJSON, XML, IWXXM |
PIREPs/AIREPs | Pilot and aircraft reports | Primarily US and North Atlantic | Raw text, JSON, GeoJSON, XML |
SIGMETs | Aviation warnings | Worldwide | Raw text, JSON, GeoJSON, XML |
G-AIRMETs | Aviation advisories | Contiguous 48 United States | JSON, GeoJSON, XML |
AIRMETs | Aviation advisories | Alaska | JSON, GeoJSON, XML, IWXXM |
CONUS text AIRMETs were discontinued in January 2025. G-AIRMETs replace AIRMETs, increasing forecast precision in both time and space. | |||
Area Forecast | Aviation forecasts | Alaska | Text |
Area Forecast Discussions | Aviation discussions | United States | Text |
Center Weather Advisories | Regional aviation advisories | United States | Raw text, JSON, GeoJSON |
Meteorological Impact Statements | Aviation statements | United States | Text |
TFM Convective Forecast (TCF) | Convective forecast | United States, portions of Canada | Raw text, GeoJSON |
Legacy wind/temp tables | Wind and temperature forecasts | United States | Text |
Station info | Weather observation station information | Worldwide | JSON, GeoJSON, XML |
Airport info | Airport information | Worldwide | JSON, GeoJSON, XML |
NAVAID, fix, feature, obstacle | Aviation navigation features | Worldwide | JSON, GeoJSON, XML |
OpenAPI
Full API specification documentation is provided in OpenAPI YAML and the following interactive interface.
Cache
The following files provide access to routinely updated full datasets. Use of these files is recommended instead of making excessively large or frequent custom queries, simplifying access to larger datasets, reducing system load, and improving access for all. All files are gzipped compressed text data.
Filename | Description | Update frequency |
---|---|---|
/data/cache/metars.cache.xml.gz | All current METARs (XML) | Once a minute |
/data/cache/metars.cache.csv.gz | All current METARs (CSV) | Once a minute |
/data/cache/tafs.cache.xml.gz | All current TAFs (XML) | Every 10 minutes |
/data/cache/airsigmets.cache.xml.gz | All current CONUS SIGMETs (XML) | Once a minute |
/data/cache/airsigmets.cache.csv.gz | All current CONUS SIGMETs (CSV) | Once a minute |
/data/cache/gairmets.cache.xml.gz | All current CONUS G-AIRMETs (XML) | Once a minute |
/data/cache/aircraftreports.cache.xml.gz | All current AIREPs/PIREPs (XML) | Once a minute |
/data/cache/aircraftreports.cache.csv.gz | All current AIREPs/PIREPs (CSV) | Once a minute |
/data/cache/stations.cache.xml.gz | Stations listing (XML) | Once a day |
/data/cache/stations.cache.json.gz | Stations listing (JSON) | Once a day |
Recent Changes
The AviationWeather Data API has been redeveloped in 2025. These improvements are intended to continue to deliver the same data with more consistent and streamlined services and documentation. External interfaces have been have been designed to retain most compability where possible however some adjustment may be required depending on specific endpoints and options used that may have been used previously. Users of the previous API should take a moment to review the new specifications and major changes outlined below.
All endpoints
- Errors with status code 400 returned for invalid input parameters
- Errors are available in plain text, JSON, and XML format
- Status code 204 returned for valid requests with no data available (except GeoJSON)
- Dates not in specific format like epoch time are returned in ISO8601 format (i.e. yyyymmddThh:mm:ss.sssZ)
- Undocumented options have been removed
/cgi-bin
- Unsupported — replaced by /api/data
- All references to cgi-bin have been removed and will no longer work
- Nearly all of the same services and options remain available through /api endpoints
- For example /cgi-bin/data/metar.php?ids=KSFO may be changed to /api/data/metar?ids=KSFO
/api/data/airport
- id property removed from JSON output
/api/data/airsigmet
- HTML format output removed
- GeoJSON format output added
- airSigmetId property removed from JSON output
- Query parameters for top, bottom, types, and loc removed
/api/data/cwa
- HTML format output removed
- GeoJSON format output added
- cwaId property removed from JSON output
- Query parameters for top, bottom, and cwsu removed
/api/data/dataserver
- Deprecated — most functionality unchanged however users are encouraged to migrate to product specific endpoints
- TAF CSV format removed
/api/data/gairmet
- HTML format output removed
- forecastId and geometryId properties removed from JSON output
- id property removed from GeoJSON output
- Query parameters for level, top, and bottom removed
/api/data/isigmet
- HTML format output removed
- isigmetId property removed from JSON output
- id property removed from GeoJSON output
- Query parameters for top and bottom removed
/api/data/metar
- HTML format output removed
- OVX returns vertical visibility as cloud base instead of zero
- metar_id property removed from JSON output
- id property removed from GeoJSON output
- Add fltCat property to JSON output
- Add clouds array to GeoJSON properties to match JSON output
- Remove individual cloud properties from GeoJSON
- Query parameters for recent, order, vfr, output, filter, and fields removed
/api/data/mis
- JSON format output added
/api/data/pirep
- pirepId property removed from JSON output
- id property removed from GeoJSON output
- Add clouds array to JSON and GeoJSON properties
- Remove individual cloud properties from JSON and GeoJSON
- Query parameters for order removed
/api/data/stationinfo
- No changes
/api/data/taf
- HTML format output removed
- Query parameters for recent, order, vfr, tempo, output, and filter removed
/api/data/tcf
- New API dataset
- TFM Convective Forecast in raw text and GeoJSON
/api/json
- Unsupported — replaced by GeoJSON services under /api/data
- For example /api/json/MetarJSON is replaced by /api/data/metar?format=geojson
Using the API
REST API endpoint are accessable at addresses under /api/data
as outlined in the schema information. For example METARs are found at https://aviationweather.gov/api/data
. Most requests require query parameters in order to specify constaints of the data being requested. For example the latest METAR from Kansas City International in JSON format can be requested by specifying the four letter ICAO identifer with https://aviationweather.gov/api/data/metar?ids=KMCI&format=json
.
Requests may be made using most web browsers, command line utilities, and programming language libraries using modern HTTPS connections.
Some parameters and response schema changed in September 2025 -- please see Recent Changes and the OpenAPI documentation.
Guidelines
- Please carefully consider requests to limit load on the system.
- Set a custom user agent to prevent automated filtering inadvertantly blocking valid traffic.
- Wait between consecutive requests — maximum 100 requests per minute.
- Exceeding request limits will result in access being temporarily blocked.
Restrictions
- All requests are rate limited to 100 requests per minute and all API endpoints should not be consumed more frequently than 1 request/min per thread.
- Most endpoints return a maximum of 400 entries (please consider using cache files for larger requests).
- Cross-origin resource sharing is not permitted at this time.
Responses
- Status code 204 is returned for valid requests with no data available (except GeoJSON).
- JSON and XML formats return standized error messages across endpoints.
- Errors are returned using standard HTTP status codes as outline in the table below.
HTTP Status Code | Description |
---|---|
204 No Content | Request is valid however there is no data to be returned. For example no recent METARs available for a particular station or no SIGMETs valid at a particular time. |
400 Invalid Request | The request is invalid in some way. This could include: Invalid parameters like format or date Missing parameters required to complete a request The URL is incorrect in some way. |
404 Not Found | The endpoint or specific item requested does not exist. |
429 Too Many Requests | Too many requests have been sent. You might see this error code when rate limits are applied. See Restrictions above. |
500 Internal Server | The request may be valid but the system was unable to serve the request due to an error. |
502 Bad Gateway 504 Gateway Timeout | Temporary service disruption. |
Troubleshooting
- Ensure your network connection is stable.
- Verify that firewalls or proxies are not blocking your requests.
- Ensure you are connecting via HTTPS.
- Some parameters and data schema changed in September 2025 -- please see Recent Changes and the OpenAPI documentation.
- See the status page for the latest updates.